Chewing gum with sustained flavor release compositions

ABSTRACT

Chewing gum with base and a flavor release composition comprising a reaction product of a polymer backbone having pendant flavor moieties thereon. The flavor moieties are released upon chewing of the gum.

nited States Patent [191 Yolles June 18, 1974 CHEWING GUM WITH SUSTAINEDFLAVOR RELEASE COMPOSITIONS Seymour Yolles, Newark, Del.

David E. Brook, Acton, Mass. a part interest Filed: Sept. 28, 1972 Appl.No.: 293,168

Inventor:

Assignee:

us. Cl. 426/3 Int. Cl A23g 3/00, A23g 3/30 Field of Search 99/135;260/66, 67, 212,

References Cited UNITED STATES PATENTS 5/1952 Heggie 99/135 2,740,7724/1956 Alfrey 99/135 Primary Examiner-A. Louis Monacell AssistantExaminer-J. M. Hunter Attorney, Agent, or FirmDavid E. Brook ABSTRACT 13Claims, N0 Drawings CHEWING GUM WITH SUSTAINED FLAVOR RELEASECOWOSITIONS BACKGROUND OF THE INVENTlON 1. Field of the Invention Thisinvention relates to sustained flavor release compositions and moreparticularly to sustained flavor release composition formed by appendingappropriate hydrolyzable flavor groups onto polymer backbones.

2. Description of the Prior Art It is known that with most flavoredchewing gums the perception of flavor drops off sharply after a shortinitial period of chewing. It has also been noted that large amounts ofthe flavor incorporated into chewing gums are retained and neverperceived by the chewer. Therefore, for chewing gum and many otherapplications, it

would be advantageous if the release of flavors could other patent,Pilotti, U.S. Pat. No. 3,011,949, it is taught that the controlledrelease of active ingredients from slab chewing gum can be achieved bycoating solid particles of active flavor ingredients with a sugarsolution, drying the coating, pulverizing the coated particles andmixing the pulverized material with the other constituents of slabchewing gum. Other techniques have been to use gelatin-coacervatedflavors (US. 2,886,449), gelatin encapsulated flavors (US. Pat. No.2,886,446), or gelatin metaphosphate encapsulated microdroplets offlavors (US. Pat. No. 2,886,444), within an all-enveloping mass ofchewable base. Despite the amount of research done to control therelease of flavors by encapsulation techniques, none of the methodspreviously known has proven successful to date.

A different technique for producing sustained release of flavors isdisclosed in Heggie, US. Pat. No. 2,596,852. By this method, permanentlyflavored gums are formed by using gum bases formed from vinyl acetatecopolymerized with vinyl unsaturated flavors. This technique, however,is severely limited by the number of vinyl unsaturated flavorsavailable, and also because incorporation of flavors into the polymerchain tends to destroy the flavor producing characteristics of theflavor monomer. That is, once incorporated as part of the polymer viavinyl polymerization, the flavor molecule is so altered as to become aninseparable part of the polymer.

There is a great need, therefore, for new flavors capable ofcontrollable sustained release.

SUMMARY OF THE INVENTION This invention relates to sustained flavorrelease compositions comprising polymer backbones with flavor groupsappended thereon. Such pendant flavor moieties are releasable from thepolymer backbone by hydrolysis. Suitable hydrolysis conditions can beachieved, for example, upon mastication of chewing gums containing thenew flavors.

Some types of pendant flavor groups included within the scope of thisinvention are acetal, hemiacetal, and ketal groups. Many common flavorsare either aldehydes, ketones or alcohols and thus lend themselves topreparation of these flavor groups.

The flavor groups can be produced directly by reacting an aldehyde orketone flavor with polymers containing hydroxy groups, or the pendantgroups can be produced by first forming acetal flavor groups andsubsequently grafting these onto various polymer backbones.

Still other flavors comprise alcohols. Alcohol flavors can be appendedonto polymer backbones using poly- DESCRIPTION OF THE INVENTION A firstclass of sustained flavor release compositions comprises those whereinacetal, hemiacetal, or ketal flavor groups are formed on polymerbackbones. Several techniques can be used to prepare this class ofmaterials.

Acetal and hemiacetal flavor groups can be tacked directly onto certainsuitable polymers. To accomplish this, aldehyde flavors are reacted withpolymers containing pendant hydroxy groups to produce the correspondingacetal or hemiacetal flavor groups. Included among suitable polymers arepartially hydrolyzed polyvinyl acetate, partially hydrolyzed copolymersof polyvinyl acetate and polyvinyl alcohol, hydroxy propyl cellulose,hydroxy propyl alginates, etc. To be suitable, of course, both thealdehyde flavors and backbone polymers must, of course, bephysiologically inert. In addition, if the flavor is to be used inchewing gum, the

"polymer should be one that is chewable or compatible with chewing gumbases. Such polymers normally have molecular weights between about 2,000and 20,000, and are well known to those skilled in the art.

The above technique is specifically illustrated by use of the followingstructural fomiulas: 1. Formation CH=CHCHO Cinnamic Aldehyde H SOCHCH;-CHCH; om-cm 2 Lin 4... l. L J.

Partial Hydrolyzed Copolymer of Vinyl Acetate and EthyleneCHCH;--OH-CH:| CI-hCH: L J L J JJH=CH Polymer with Pendant Cinnamic WCyclic Acetal Flavor Group CH=CH-CHO I Lam in it J.

In a second method of preparing acetal and ketal pendant flavor groups,epichlorohydrin or epibromohydrin is used. The aldehyde or ketone flavoris reacted with epichloroor epibromohydrin to produce a chloroorbromopropyl ketal or acetal. This can then be reacted with polymershaving sodium metal ions associated therewith. Suitable polymers includesodium alginate, sodium starch, sodium carboxymethylcellulose,copolymers of sodium polyacrylates, salts of pectin and pectic acid,etc.

This method of preparing pendant acetal and ketal flavor groups can bespecifically illustrated with the use of the following-structuralformulas:

g: ca,

Oopolymer with Pendant Menthone Ketal A second indirect method forproducing the acetal or ketal flavor groups and subsequently graftingthem onto polymer backbones is as follows. ln this method, an aldehydeor ketone flavor is reacted with a polyhydric alcohol such as glycerineto produce the corresponding acetal or ketal of the flavor with an extrapendant hydroxide group. The acetal or ketal flavor is then reacted witha polymer having pendant esters of carboxylic acid groups. In thismethod, basic catalysts such as lithium methoxide and lithium hydrideare used. It is important to be able to use these basic catalysts, andthat is why the ester of the carboxylic acid is used rather than thefree acid, because acidic catalysts such as sulfuric acid, althoughcapable of catalyzing such al coholyses, also catalyze the opening andbreaking of the cyclic acetal flavors. Thus, the flavor acetal or ketalgroups can be destroyed if basic catalysts are not used.

This method is illustrated specifically with the following structuralformulas:

Acrylate and Ethylene Cyclic Acet-al of Glycerine and Cinnamic AldehydeP en dant. C yclic Acetal on Copolymer Backbone The above techniquesutilize aldehyde or ketone fla vors. Examples of aldehyde flavorsinclude: acetaldehyde (apple); benzaldehyde (cherry, almond); anisicaldehyde (licorice, anise); cinnamic aldehyde (cinnamon); citral, i.e.alpha citral (lemon, lime); neral, i.e. beta citral (lemon, lime);decanal (orange, lemon); ethyl vanillin (vanilla, cream); heliotropine,i.e. piperonal (vanilla, cream); vanillin (vanilla, cream); a-amylcinnamaldehyde (spicy fruity flavors); butyraldehyde (butter, cheese);valeraldehyde (butter, cheese); citronellal (modifies, many types);decenal (citrus fruits); aldehyde C-8 (citrus fruits); aldehyde C-9(citrus fruits); aldehyde C- l 2 (citrus fruits); Z-ethyl butyraldehyde(berry fruits); hexenal, i.e. trans-2 (berry fruits); tolyl aldehyde(cherry, almond); veratraldehyde (vanilla); 2,6-dimethyl-5-heptenal,i.e. Melonal (melon); 2,6-dimethyloctanal (green fruit); and,2-dodecenal (citrus, mandarin). Examples of ketone flavors include:d-carvone (caraway); l-carvone (Spearmint): diacetyl (butter, cheese,cream"); benzophenone (fruity and spicy flavors, vanilla); methyl ethylketone (berry fruits); maltol (berry fruits) menthone (mints) methylamyl ketone, ethyl butyl ketone, dipropyl ketone, methyl hexyl ketone,ethyl amyl ketone (berry fruits, stone fruits); pyruvic acid (smokey,nutty flavors);

Copolymer of Aerolein and Methyl Methaerylnte Pendant MentholHemi-Acetal on Copolymer Backbone Some specific examples of alcoholflavors include: anisic alcohol or p-methoxybenzyl alcohol (fruity,peach); benzyl alcohol (fruity); Carvacrol or 2-pcymenol (pungent warmodor); carveol; cinnamyl alcohol (floral odor); citronellol (rose like);decanol; dihydrocarveol (spicy, peppery); tetrahydrogeraniol or 3,7-dimethyl-l-octanol (rose odor); eugenol (clove); and,p-mentha-l,8-dien-7-Ol or perillyl alcohol (floralpine).

The sustained flavor release compositions described herein areespecially useful in chewing gums. Customarily, chewing gums containchewing gum base, flavor, sweetener, filler, and certain other optionalingredients.

Chewing gum bases are usually resinous materials and should benon-toxic, clean, odorless, tasteless, colorless, nonsticky, elastic,economical, insoluble in water, resistant to decomposition anddepolymerization, resistant to oxidation and embrittlement upon aging,resistant to conversion into toxic products and resistant to flavordissipation, etc. The primary requirement is, of course, that theyimpart a permanent chewability to the chewing gum composition. Manynatural and synthetic resins have been'utilized as chewing gum bases.Chickle is the most widely used natural resin whereas homoand copolymersof vinyl acetate, sometimes partially hydrolized, are examples ofsynthetic chewing gum bases. These bases and others customarily used canbe used with the sustained flavor release compositions described hereinto form chewing gums.

Suitable sweetening agents include sucrose, dextrose, invert sugar,honey, levulose, saccharin, cyclamates, etc.

In like manner, fillers customarily used are also satisfactory. Mineralfillers are used which are finely ground, inert, non-toxic, tastelessand not exceedingly abrasive. In addition, they must not crumble duringthe chewing process. Inert pigments may also be incorporated into thechewing gum formulations as part of the filler content in order to colorthe mix. Typical inert pigments and filler materials include:precipitated chalk, clay, barium sulfate, magnesium oxide, silica, talc,carbon black, iron oxide, yellow ochre, magnesium carbonate, calciumsulfate, etc.

Optional additives such as waxes used to lubricate and facilitate thehigh speed manufacturing process, conditioning agents such as glycerineand propylene glycol, and various medicinal compounds, etc., can, ofcourse, be added to the chewing gum compositions described herein.

The known methods for the preparation of conventional chewing gumproducts may be employed in preparing chewing gums of this invention. Ingeneral, one or more blending operations is required which may becarried out at elevated temperatures followed by the introduction of thehomogeneous mass into a mill which forms gum sheets which aresubsequently cut into chewing gum sticks. I T

The proportions of the various ingredients will vary over wide rangesaccording to the final taste desired In general,however, it has beenfound that suitable chewing gums can be prepared using the controlledrelease flavors of this invention in amounts ranging from about 5percent to about 20 percent by weight.

When used in chewing gum or other flavored products, the sustainedflavor release compositions described herein can, of course, be combinedwith other flavors which may or may not be controllably released. Forexample, chewing gum formulations can be prepared using some of thecontrolled release flavors described herein as well as some naturalflavors and might even include some of the flavors encapsulated by priorart methods.

The following examples further illustrate the invention. All parts andpercentages are by weight unless otherwise specified.

EXAMPLE 1 Preparation of the Cyclic Acetal of Cinnamic Aldehyde andGlycerin In a one-liter,. three-neck round bottom flask equipped with awatercooled condenser, stirrer, and a water separator, 66 g. of cinnamicaldehyde is added to 46 g. of glycerin in 200 ml. of dry benzenecontaining 2 g. of polyphosphoric acid. After 6.5 hours, 8.5 ml. ofwater are removed from the separator and 200 ml. additional benzene isadded to the reaction mixture. After washing with 300 ml. of 1 percentsodium hydroxide solution and rinsing until neutral, the mixture isfiltered and the benzene is removed under vacuum. The light yellow solidis then vacuum distilled.

Product identification is based on IR, which shows no carbonylfrequency, and mass spec.

Boiling point at 1.8 mm. Hg, Molecular Weight by Mass Spec. 206.

.The cyclic acetal so prepared can be named 2-(13- styryl l,3-dioxolane-4-methanol.

EXAMPLE 2 Alcoholysis to Tack Cyclic Acetal onto Polymer Backbone Al28.2g sample of dried ethyl acrylate-ethylene copolymer containing 50mole percent ethylacrylate prestirred with 206.3 g. of Z-(B-styryD-l,3-dioxolane-4- methanol as prepared in Example 1. To this solution isadded 2.0 g. of lithium methoxide and the reaction mixture is brought toreflux. After one hour, collection of ethanol distillate is started andcontinued until the risein boiling point indicates that no more ethanolis being collected. Close to 46 g. of ethanol, the nearly theoreticalamount is obtained. After filtering, the reaction mixture is stripped oftoluene at reduced pressure leaving 288.0 g. of an off-white resin. Thisresin, without further treatment, can be incorporated in chewing gum tothe extent of 6 to percent by weight to provide a cinnamon flavor uponmastication of the gum.

EXAMPLE 3 Alternative Alcoholysis for Tacking Cyclic Acetal onto PolymerBackbone A 40 g. sample of citrus pectin NF. in which a high proportionof the D-galacturonic acid moieties are present as methyl esters isdried in a vacuum oven at 50C. for six days followed by removing thelast traces of water with a Dean-Stark trap and refluxing benzene. Thereaction mixture is then treated with 17.0 g. of 2-(fi-styryU-l,3-dioxolane-4-methanol (Example 1), 3.0 g. of sodiummethoxide, and brought to reflux for one hour. With the condenser setfor downward distillation, benzene and methanol are distilled and theprocess continued until tests of the distillate with 2,4- dinitrobenzoylchloride show that no more methanol is being generated. The solidprecipitate is filtered from the reaction mixture and dried undervacuum. The powder can be incorporated into chewing gum in amounts of6-10 percent to provide the slow release of cinnamon flavor on chewing.

EXAMPLE 4 Reaction of Hydroxypropyl Cellulose and Cinnamic Aldehyde toTack Acetal onto Polymer Backbone in a 100 X 50 mm. crystallizing dish,6.7 g. of Klucel hydroxypropyl cellulose (Hercules type EF) and 3.7 g.of cinnamic aldehyde are thoroughly mixed. The mixture is kneaded with aspatula to a dough. ln portions, 0.5 ml. of 33 percent by volume HCIsolution is worked in. The dough is then pressed between glass platesinto a film and the film allowed to stand under nitrogen 24 hours. Thefilm is then placed under vacuum at 80C. for a four-hour period. Aftercooling, the product is ground to a coarse powder in a blender.

EXAMPLE 5 Preparation of Chewing Gum from Acetal of Klucel and CinnamicAldehyde Chewing gum base is melted in a small double boiler, and thetemperature is maintained at approximately 47C. throughout theformulation.

Materials (In Order of Addn.) Amount in Grams gum base 2 corn syruppowdered sugar 1 l'umaric acid glycerin/water (50/50) corn oil flavor(Ex. 4)

The hot mixture is poured onto a Mylar sheet and rolled between twoMylar sheets. The g um isther frozen and the Mylar removed. This gumexhibits good flavor release after chewing for one hour.

EXAMPLE 6 Preparation of Copolymer of Acrolein-Methyl Me thacrylate.

A two-liter resin kettle equipped with mechanical stirrer, condenser andnitrogen gas inlet is charged with 72.1 g. methyl methacrylate, 10.1 g.acrolein and 23.2 ml. ethyl acetate. The solution, stirred and heated to90C. under nitrogen atmosphere, is treated with 1.21 g. Vazo in 13.5 ml.of ethyl acetate. To this reaction mixture there is added slowly over a50-minute period 168.1 g. methyl methacrylate, 23.5 g. acrolein, 2.3 g.Vazo catalyst in 156 ml. ethyl acetate. The mixture is stirred for anadditional hour at 90C. becoming viscous and cloudy. With the refluxcondenser set for downward distillation, solvent and unreacted monomersare distilled out.

The clear, viscous resin is dissolved in 250 ml. of fresh ethyl acetate.The cooled solution is stirred with a saturated solution of sodiumhydrogen carbonate until foaming subsides. The mixture is transferred toa two-liter preparatory funnel and the water layer removed. The reactionmixture is washed again with 300 ml. of water and after separation thewhite viscous resin layer is subjected to low pressure in a vacuumdesiccator to remove the last traces of solvent. The white brittle solidweighed 219.1 g. (an 80 percent yield) and contained 20 mole percent ofgroups. Analysis by infrared spectroscopy confirms the presence ofaldehyde groups.

EXAMPLE 7 Preparation of Acetal of Methyl Acrolein Copolymer A 91.29 g.sample of dried copolymer (Example 6) is stirred with 300 m1. oftoluene, 34.86 g. of hydroxycitronellol, 2 g. of polyphosphoric acid,for two hours at C. After standing overnight at room temperature, thebatch is washed two times with 200 ml. portions of saturated sodiumhydrogen carbonate followed by water washing. When the solvent tolueneis removed under reduced pressure, a brittle resin remains. l. R.spectroscopy confirms that most of the aldehyde groups have beenconverted to acetal and/or hemiaceta] groups. When this resin isincorporated in chewing gum and chewed, a flavor reminiscent of hyacinthrose and grape is slowly released.

EXAMPLE 8 Alternate Method of Acetal Preparation In a 100 X 50 mm. dish,9.13 g. of methyl methacrylateacrolein copolymer is thoroughly mixedwith 3.1 g. of l-menthol and formed into a dough with a minimum amountof dioxane. ln portions, 0.5 ml. of 33 percent hydrochloric acid isworked into the dough. The dough is then pressed into a film betweenglass plates and allowed to remain under nitrogen for 24 hours. The filmis then subjected to low pressure at C. for a four-hour period when mostof the solvent, water and Methacrylatehydrogen chloride leave. Aftercooling, the product is ground to a coarse powder. Infrared spectroscopyconfirms the disappearance of aldehyde groups.

What is claimed is:

1. Chewing gum comprising a chewing gum base and a controlled flavorrelease composition which is a reaction product of a polymer backbonewhich is physiologically inert, chewable and compatible with saidchewing gum base and flavor compounds producing pendant flavor moietieson the polymer which are releasable from said polymer backbone uponmastication of said chewing gum.

2. Chewing gum of claim 1 wherein said pendant flavor moieties compriseacetal, hemiacetal or ketal groups.

3. Chewing gum of claim 2 wherein said pendant flavor moieties compriseacetal or hemiacetal groups formed by reacting aldehyde flavors with apolymer backbone having pendant hydroxy groups thereon.

4. Chewing gum of claim 3 wherein said polymer backbone comprisespartially hydrolyzed homopolymers or copolymers of vinyl acetate,hydroxy propyl cellulose, hydroxy propyl alginate or polyvinyl alcohol.

5. Chewing gum of claim 4 wherein said aldehyde flavor comprisesacetaldehyde, benzaldehyde, anisic aldehyde, cinnamic aldehyde, alphacitral, beta citral, decanal, vanillin, ethyl vanillin, heliotropine,a-amyl cinnamaldehyde, butyraldehyde, valeraldehyde, citronellal,decenal, aldehyde C-8, aldehyde C-9, aldehyde C-l2, 2-ethylbutyraldehyde, hexenal (trans-2), tolyl aldehyde, veratraldehyde,2,6-dimethyl-5-heptenal, 2,6-dimethyl-octanal; and, Z-dodecenal.

6. Chewing gum of claim 5 wherein said controlled flavor releasecomposition is present in an amount of from about 5 percent to about 20percent by weight of said chewing gum composition.

7. Chewing gum of claim 1 wherein said pendant flavor moieties compriseketal groups formed by reacting ketone flavors with a polymer backbonehaving hydroxy groups thereon.

8. Chewing gum of claim 7 wherein said polymer backbone comprisespartially hydrolyzed homopolymers or copolymers of vinyl acetate,hydroxy propyl cellulose, hydroxy propyl alginate or polyvinyl alcohol.

9. Chewing gum of claim 8 wherein said ketone flavor comprisesd-carvone, l-carbone, diacetyl, benzophenone, methyl ethyl ketone,maltol, menthone, methyl amyl ketone, ethyl butyl ketone, dipropylketone, methyl hexyl ketone, ethyl amyl ketone, pyruvic acid,acetanisole, dihydrocarvone, 2,4- dimethylacetophenone, l,3-diphenyl-2-propanone, acetocumeme, isojasmone, d-isomethylionone,isobutyl acetoacetate, zingerone, pulegone, d-piperitone; and,2-nonanone.

l0. Chewing gum of claim 9 wherein said controlled flavor releasecomposition is present in an amount of from about 5 percent to about 20percent by weight of said chewing gum composition.

11. Chewing gum of claim 1 wherein said acetal, hemiacetal or ketalpendant flavor moieties are formed by reacting an alcohol falvor with apolymer having pendant aldehyde or ketone groups thereon.

l2. Chewing gum of claim 11 wherein said alcohol flavor comprises anisicalcohol (p-methoxybenzyl alcohol); benzyl alcohol; carvacrol(2-p-cymenol); carveol; cinnamyl alcohol; citronellol; decanol;dihydrocarveol; tetrahydrogeraniol 3,7-dimethyl-l-octanol; eugenol;p-metha l ,8-dien-8-ol( perillyl alcohol).

13. Chewing gum of claim 12 wherein said polymer backbone comprises apolymer formed from acrolein.

2. Chewing gum of claim 1 wherein said pendant flavor moieties compriseacetal, hemiacetal or ketal groups.
 3. Chewing gum of claim 2 whereinsaid pendant flavor moieties comprise acetal or hemiacetal groups formedby reacting aldehyde flavors with a polymer backbone having pendanthydroxy groups thereon.
 4. Chewing gum of claim 3 wherein said polymerbackbone comprises partially hydrolyzed homopolymers or copolymers ofvinyl acetate, hydroxy propyl cellulose, hydroxy propyl alginate orpolyvinyl alcohol.
 5. Chewing gum of claim 4 wherein said aldehydeflavor comprises acetaldehyde, benzaldehyde, anisic aldehyde, cinnamicaldehyde, alpha citral, beta citral, decanal, vanillin, ethyl vanillin,heliotropine, Alpha -amyl cinnamaldehyde, butyraldehyde, valeraldehyde,citronellal, decenal, aldehyde C-8, aldehyde C-9, aldehyde C-12, 2-ethylbutyraldehyde, hexenal (trans-2), tolyl aldehyde, veratraldehyde,2,6-dimethyl-5-heptenal, 2,6-dimethyl-octanal; and, 2-dodecenal. 6.Chewing gum of claim 5 wherein said controlled flavor releasecomposition is present in an amount of from about 5 percent to about 20percent by weight of said chewing gum composition.
 7. Chewing gum ofclaim 1 wherein said pendant flavor moieties comprise ketal groupsformed by reacting ketone flavors with a polymer backbone having hydroxygroups thereon.
 8. Chewing gum of claim 7 wherein said polymer backbonecomprises partially hydrolyzed homopolymers or copolymers of vinylacetate, hydroxy propyl cellulose, hydroxy propyl alginate or polyvinylalcohol.
 9. Chewing gum of claim 8 wherein said ketone flavor comprisesd-carvone, 1-carbone, diacetyl, benzophenone, methyl ethyl ketone,maltol, menthone, methyl amyl ketone, ethyl butyl ketone, dipropylketone, methyl hexyl ketone, ethyl amyl ketone, pyruvic acid,acetanisole, dihydrocarvone, 2,4-dimethylacetophenone,1,3-diPhenyl-2-propanone, acetocumeme, isojasmone, d-isomethylionone,isobutyl acetoacetate, zingerone, pulegone, d-piperitone; and,2-nonanone.
 10. Chewing gum of claim 9 wherein said controlled flavorrelease composition is present in an amount of from about 5 percent toabout 20 percent by weight of said chewing gum composition.
 11. Chewinggum of claim 1 wherein said acetal, hemiacetal or ketal pendant flavormoieties are formed by reacting an alcohol falvor with a polymer havingpendant aldehyde or ketone groups thereon.
 12. Chewing gum of claim 11wherein said alcohol flavor comprises anisic alcohol (p-methoxybenzylalcohol); benzyl alcohol; carvacrol (2-p-cymenol); carveol; cinnamylalcohol; citronellol; decanol; dihydrocarveol; tetrahydrogeraniol3,7-dimethyl-1-octanol; eugenol; p-metha-1,8-dien-8-ol(perillylalcohol).
 13. Chewing gum of claim 12 wherein said polymer backbonecomprises a polymer formed from acrolein.